Got a question thats been bothering me...

[ProjectWE4]

What does this do exactly and how do they compare to each other.. when im mean what do they do. what does it look at or controll or if any of that.. im just trying to learn about the electronics for later use.. and could they be used with not a big setup
F.A.S.T- Custom installation/ Performance tuning/ Start-up programs & tuning over the internet

DFI-Custom installation/ Performance tuning
thanks...

 

[bobc455]

Could you re-state the question? I'm not sure I follow you.

-Bob Cunningham

 

[Chuck Leeper]

WHAT??

Originally posted by bobc455
Could you re-state the question? I'm not sure I follow you.

-Bob Cunningham

I'm like you on this one, Bob!!
WE, what are you talking about?? I've re-read this post at least 4 times, and yet have to make any sense of it.....

 

[ProjectWE4]

i meant what do these systems do for our cars.

like what does it controll and how..

hey im sorry i dont know much about these system things.. so im just trying to learn

thanks

 

[bobc455]

Basically the ECU has inputs and outputs.

Inputs:
- RPM
- Throttle Position
- Manifold pressure or mass airflow
- Engine temperature
- some other stuff too

Then, based on those inputs, the ECU makes some decisions and sends outputs:
- How long and when to open the fuel injectors
- When to fire the spark plugs
- Where to put the idle air control motor
- Some other stuff too

The ECU has to be programmed to know how to react- for example it has to know that a 50# injector requires less opening time than a 36# injector. There are some huge, complex formulas that the system goes through to arrive at the outputs. On a new car, the computer comes pre-programmed to handle these things, but if we start changing things (bigger turbo, different injectors, etc.) then somehow we need to re-program the computer accordingly. The aftermarket computers (FAST, DFI, etc.) are generally user-programmable to take care of these functions.

Make sense?

-Bob Cunningham

 

[RickWI]

It's the electronic version of carburator and distributor tuning kits of the past. Only these cost a bit more.